Vermont State Butterfly Proposed for Threatened Species Listing

Female Monarch Butterfly nectaring in the morning sun preparing for a day of migration © Kent McFarland

Close your eyes and shift your mind away from the chilly landscape out your window. Take yourself back to a bright midsummer day. You’re in a field dotted with wildflowers. The sun is warm; the breeze is light. You let your vision soften out to the horizon and notice a large orange and black butterfly perched on flowering milkweed. The Monarch lets you approach and watch it momentarily before it takes flight toward the end of the field.

For those who have spent their summers in Vermont, this scene was probably conjured as much from memory as imagination. We welcome Monarchs each year as a signal that deep summer is upon us. These charismatic insects are so iconic that we honor them as the state butterfly.

Monarchs in Decline

However, concerns about migratory Monarch populations have been growing, with good reason, for years. In the 2023–2024 winter, researchers measuring eastern migratory Monarch populations on their overwintering grounds in Mexico recorded butterflies on only 2.2 acres of land, the second smallest total overwintering area occupied since monitoring began in 1993 (see full article). This represents a 59% decline compared to the previous winter and a 95% decline compared to the largest total area occupied (45 acres) in the winter of 1996–1997. According to the most recent Monarch Species Status Assessment conducted by the U.S. Fish & Wildlife Service (USFWS), eastern migratory Monarchs face a 56 to 74% probability of extinction by 2080.

So, what does this mean for Vermont?

“I frequently hear people say, ‘But I see them everywhere!’, which is often true,” says VCE conservation biologist and Vermont Atlas of Life director Kent McFarland. “Monarch populations can really fluctuate depending on the conditions. It could be rare one year and everywhere the next.”

For the many of us who have not given Monarch biology a second thought since we left grade school, here is a quick crash course. These insects produce multiple generations during the Northeast’s warm months, with each adult living two to five weeks on average. That is until their final summer generation, which serves as an exception to this two- to five-week lifespan. Instead of following the same reproduction timeline, these adults forgo mating to journey thousands of miles south to Mexico, where they spend the winter relatively inactive. In late winter (typically February or March), these Monarchs finally mate and begin traveling northward. Along the way, the females stop and lay their eggs on milkweed, and this old generation (having survived six to nine months!) dies off. Their offspring continue north, spreading throughout most of the eastern U.S. and southern Canada in two to three generations and making Monarchs an outstanding recolonization phenomenon unrivaled by other insects. You can read more about Monarch life cycles by reading naturalist and journalist Bryan Pfeiffer’s article reflecting on their proposed listing and spectacular migration.

How many Monarchs we see in Vermont this summer depends on many factors beyond our borders. The number journeying north to New England is affected by weather patterns and habitat suitability on their wintering grounds, as well as conditions along their migratory corridors. Yearly fluctuations in the number of Monarchs that make their way north are normal. Multi-decade declines are not.

“It’s unlikely that Monarchs as a species will go extinct in the foreseeable future,” says McFarland. Non-migratory Monarch populations exist throughout the southeastern U.S. and Caribbean. “But the migratory phenomenon could disappear. And if the migration disappears, they will disappear from Vermont.”

Monarchs roosting for the night on Monhegan Island before continuing their migration south © Michael Sargent

USFWS Proposes Threatened Species Listing

Species declines on such a broad geographic scale require federal action. On December 12, 2024, just over a decade after the original petition was filed, USFWS officially proposed Monarchs be listed as a Threatened species under the Endangered Species Act (ESA). Currently, their proposed rule is subject to a 90-day public comment period. During this time, anyone can share their perspective on the proposal directly with the agency. The public comment period closes on March 12, 2025.

The ESA directs the Secretary of the Interior to use the best available evidence to determine whether or not a listing is warranted. In their proposed rule, USFWS cites several well-documented threats to the persistence of migratory Monarch populations: the ongoing impacts from loss and degradation of breeding, migratory, and overwintering habitat; exposure to pesticides; and effects of climate change. For the eastern migratory population, USFWS points explicitly to the decline of milkweed due to land use change and herbicides, as well as the loss of suitable overwintering habitat and climate change.

During the public comment period, USFWS seeks more information to either support or refute the basis for their listing. However, they’re also looking for opinions and insights on addressing certain protections or exemptions Monarchs might receive.

Now, you may wonder, “But if it’s listed, won’t it just be ‘protected’?”

Protection under the ESA looks slightly different depending on whether a species is listed as Endangered or Threatened. Endangered species automatically receive protection under section 9 (read the full language). For Threatened species, however, things operate a little differently. Their protection comes from section 4(d), leading Threatened species guidelines to be known as their “4(d) rule.” Section 4(d) is fairly flexible, allowing the USFWS to tailor rules that are “necessary and advisable to provide for the conservation of such species.” Thanks to something known as “the blanket rule” (which was reinstated in 2024 after the first Trump administration removed it), Threatened species automatically receive the same protection that Endangered species do. Beyond that, the USFWS can determine special rules and exemptions that apply to that species and its unique circumstances. You can learn more about 4(d) rules on the USFWS FAQ page.

For Monarchs, USFWS aims to use the 4(d) rule to increase the availability of milkweed and nectar plants in breeding and migratory areas, protect and enhance overwintering habitat, and support the public in helping advance Monarch conservation. Conservation outcomes are their main goal; however, conservation is always a balancing act, and the rule does contain some exceptions. The specific exceptions include activities that may affect milkweed but do not result in the conversion of native or naturalized habitats or Monarch mortality due to vehicle strikes.

Monarchs offer people of all ages the opportunity to learn about nature and butterfly lifecycles. That’s why USFWS specifically allows non-lethal research and education activities under their proposed rule. © Michael Sargent

Given Monarchs’ prevalence as a teaching tool, another key exception is for non-lethal collection, possession, captive-rearing, and release of 250 (or fewer) Monarchs per year. USFWS specifically includes both non-lethal scientific research and educational activities in this allowance. Please visit the Monarch 4(d) Rule FAQ page for a complete list of prohibitions and exceptions.

However, one major question looms over the Monarch’s 4(d) rulemaking: how should USFWS handle pesticides? Should they include exceptions for pesticide usage? The Service is specifically looking for feedback on this question in public comments. You can read more about pesticides and Monarchs from the Monarch Joint Venture.

After the comment period closes on March 12, 2025, USFWS will spend the rest of the year reviewing public input and developing its final rule. If the Secretary of the Interior chooses to move forward with the listing, Monarchs will be protected once the final rule is published. After that, the Secretary of the Interior will develop and implement a recovery plan for the species, unless a recovery plan is deemed unnecessary.

A Monarch caterpillar notches a milkweed leaf to help slow the flow of sap before feeding. An unhatched egg is stuck to the underside of the leaf near the end of the caterpillar. / © K.P. McFarland

Conservation Takes All of Us

Sometimes, tackling enormous environmental issues, like recovering a species headed toward extinction, can feel daunting, even hopeless. However, the ESA—when implemented effectively—can yield tremendous results. Just this past year, the Red-cockaded Woodpecker was downlisted from Endangered to Threatened after decades of conservation efforts. (Read the full USFWS press release.) Here in Vermont, Common Loons rebounded from seven nesting pairs in the 1980s to over 100 today. In both these cases, success is attributed to targeted conservation strategies, careful monitoring, and, above all, a collaborative network of dedicated government staff, academics, nonprofits, and community members. If granted protection under the ESA and bestowed with a robust recovery plan, Monarchs could be the next conservation success story and continue to grace Vermont’s meadows for generations to come.

Are you wondering what you can do to help Monarchs? Many opportunities abound!

If you want to share your thoughts on Monarch’s proposed ESA listing, make sure to submit your written comments by March 12, 2025. Follow the instructions under “Addresses” on the Proposed Rule page. The Monarch Joint Venture has an excellent list of resources describing how to approach public comments at the bottom of this page.

You can support your own local Monarchs during their summer visits by creating pollinator-friendly spaces. The Monarch Joint Venture has a lot of informative resources, including this handout about mowing and Monarchs.

Finally, you can become a community scientist and help researchers collect valuable data on Monarchs and other butterflies. VCE is currently in the middle of our second Vermont Butterfly Atlas, which allows us discover how butterfly populations are changing over time. You can also participate in Mission Monarch and share your Monarch (and other butterfly!) observations through eButterfly.